The present invention concerns a roof construction, in particular a self-supporting roof construction, with several erected support arches carrying a tentered roof skin, both ends of said support arches being held with a fixed distance to one another in the carrying state.
Such roof constructions are, for example, known for tents, where the tent roof is supported and held in shape via tubular support arches. Such support arches are usually put together from several sections and erected on the spot, and can carry, with suitable anchoring, for example at the ground of the tent, the tent roof in a supporting fashion due to their flexural strength.
For larger tent roofs such a construction, as it is known for relatively small tent roofs, is not possible anymore since the flexural strength of the support arches is not sufficient anymore to be able to take up the weight of the tent roof resting on them. Furthermore, for larger roof constructions, the relatively long support arches would have to be disassembled for transport and then put together again on the spot, which would involve expensive assembly and disassembly efforts as well as a large expenditure of time.
Hence it is the object of the present invention to further develop a roof construction of the aforementioned type such that with simultaneously fast and simple dismounting and mounting also roof constructions with relatively long support arches can be carried safely.
This object is solved according to the invention in that each support arch is constituted by several sections each connected to one another via joints, where a lock is assigned to each joint, which limits the unfolding of neighboring sections to about their straightened position, and that in the carrying state of the support arch all its joints are bridged underneath by tensioned pulling connections, which engage on both sides of the bridged joint on a section and that in the region of each joint a spacer is provided acting between the support arch and the corresponding pulling connection, which spacer directs the pulling connection inwards past the connecting line defined by the two points of engagement.
This roof construction has the essential advantage that the support arches can be easily folded together via their joints and can thus be erected on the spot into their preferably arc-shaped final position by unfolding. In order for an erected support arch not to disintegrate due to its own weight and the weight of the roof skin bearing on it, each pulling connection tensioned beneath a joint is spaced thus far towards the inside by the associated spacer that the tensile force acting between two points of engagement on the support arch comprises on the spacer also a component directed outwards towards the joint, which component can take up the forces acting on the joint towards the inside. Furthermore, the inventive roof construction can be quickly and easily assembled and disassembled due to the unfolding and folding of the support arches.
In preferred embodiments of the invention, the erected support arches are disposed in longitudinal direction behind one another or in pairs in order to stiffen the roof construction in longitudinal direction, where neighboring erected support arches support each other in pairs.
Neighboring erected support arches can cross each other either in pairs in the crown area by supporting each other, or they touch each other in pairs in the crown area, which is a preferred development. In the latter case, the roof construction or the roof skin is stiffened in longitudinal direction via the crowns of the support arches touching in pairs.
In a further preferred embodiment, the two ends of a support arch are fixed, in particular hinged, to parts which can be moved outwards, preferably can be hinged down. By tilting the parts, which determine the distance between the two ends of the support arch, this distance enlarges, thus the sections of the support arch can be at least partially unfolded in direction to its straightened or arc-shaped final position if the sections are, for example, folded like a bellow. Preferably the parts which can be tilted outwards are side walls or ceiling parts of a vehicle body.
As an advantageous development of this embodiment it is provided that parts that are moved outwards, preferably hinged down, and are fastened in this state form a base of the roof construction. This has the advantage that not only the sections of a support arch, but at least also a part of the base is designed foldable. Hence, the space required by the roof construction together with its base in the folded state can be kept particularly small.
In particularly preferred embodiments, sections of a support arch, preferably all of its sections, can be folded between parts put upright. By moving or hinging down and outwards of the parts, these sections of a support arch, in particular folded together like a bellow, can then be pulled apart and unfolded outwards towards the erected support arch. Then the support arch can be transferred into its completely erected final position manually by a person, by whom the formation of the individual pulling connections can also be initiated.
In particularly preferred embodiments of the inventive roof construction the pulling means provided on a support arch are formed by a single common pulling rope. If the support arch was partially or already completely unfolded in its unfolded final position, this pulling rope tensioning all the sections of a support arch underneath is tightened, thus the individual sections are tensioned in their final positions in which they can support their own weight and that of the roof skin. The pulling rope is deviated in the area of the joints towards the inside by the spacers. The pulling rope is preferably held in corresponding guides on the sections and on the spacers, and that also in the folded state of the support arch. For example, by means of a hydraulic pulling device, which engages on one end of the pulling rope, this can be tightened and tensioned.
The sections are fiber-enforced, in particular by glass material, or completely made from glass fiber material, in order to increase the tensile and flexural strength as well as the stability of shape and stability of the sections or of the erected support arch. The use of fiber material for the sections has the additional advantage, in contrast to rigid sections, that the support arch can be better adjusted to the contour of the tentered roof skin.
The roof skin is preferably connected to the support arches permanently and can be folded, for example like a bellow, as well as unfolded with the support arches. The roof skin is preferably designed as light permeable membrane, in order to illuminate the inner space covered by the membrane with daylight.
In particularly preferred embodiments of the invention, the base of the roof construction is formed by a loading area and by parts of a vehicle which can be hinged outwards onto the level of the loading area, in particular by side walls of a lorry. The roof construction can then be used flexibly and variably as a mobile unit, for example, as surface mounting on a lorry. This driveable unit can be quickly transferred, for example, into a sheltered, temporary exhibition area by a transformation on the vehicle.
As advantageous further development of this embodiment a substructure can be provided which supports the base of the roof construction about on the level of the loading area of the vehicle. This substructure can, for example, be formed by base supports, which support the hinged down side walls of the vehicle. If additionally also the loading area is supported by a suitable substructure, the vehicle can be detached from the loading area and the side walls and removed underneath those, if the base of the roof construction is formed and supported.
If the roof construction tensioned underneath should not be visible from the inside by an observer, a textile inner covering can be held in a hanging fashion on the support arches, and that in particular on the spacers, with the roof construction being erected.
The present invention also concerns a vehicle with a loading area and with a roof construction, as described earlier, roofing over this loading area in the unfolded state. For example, as surface mounting on a vehicle the roof construction can be used as mobile unit flexibly and variably, in particular for a traveling exhibition. By the transformation on the vehicle this driveable unit can be quickly transferred, for example, into a covered, temporary exhibition area and thus be integrated variably in a town landscape.
Such a vehicle can be quickly transformed into a roofed over space, since the roof construction can be folded between two upright side walls, in particular side walls which can be put upright, of the vehicle. The unfolding of the roof construction can be initiated, as described earlier, by hinging down the side walls.
In a further advantageous embodiment of the inventive vehicle the two outer sections of a support arch are hinged to ceiling parts, which are themselves hinged moveably, preferably flapably, to the vehicle. These ceiling parts, which can form, for example, the vehicle roof with the roof construction being folded together, can be hinged to side walls of the vehicle which can be hinged down.